Method of manufacturing rolling bearing components

ABSTRACT

A method of manufacturing rolling bearing components consisting of the steps of forming a tubular member by bending up a flat sheet and joining the sheet at confronting edges, separating the tubular member into a plurality of annular rings, and simultaneously rolling and bending at least one flange at one end of said annular ring at grooved portions formed by rolling.

United States Patent Stig Lennart Hallerback Blodboksgatan 12, VastraFrolunda, Sweden Aug. 2, 1968 May 25, 1971 Inventor Appl. No. FiledPatented METHOD OF MANUFACTURING ROLLING BEARING COMPONENTS 6 Claims, 8Drawing Figs.

US. Cl 29/ 148.4, 29/417 Int. Cl B23p11/00, B23p 17/00 Field of Search29/1484,

149.5, 148.4 (C), (Bend), (Roll), 417; 113/1 17 [56] References CitedUNITED STATES PATENTS 2,591,160 4/1952 Kilian 29/148.4X 2,719,76510/1955 Menne 29/1484 2,737,707 3/1956 Highet et a1. 29/1495 PrimaryExaminer-Thomas H. Eagen Attorneyl-lowson and Howson I PATENTEDmzsmn3579782 sum 1 or '2 FIG. i.

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INVENIOR. STIG LENNART HALL ER BACK ATTYS.

METHOD OF MANUFACTURING ROLLING BEARING COMPONENTS The present inventionrefers to a novel and improved method of manufacturing rolling bearingcomponents.

According to previously used methods forthe manufacture of, for example,race rings for rolling bearings, tubular elements are cut from steeltubes or bars in a suitable manner, whereupon these elements are workeduntil a ring of approximately the desired dimensions is obtained. Whenthe ring is intended to be used in ball bearings, the working will alsoinclude the shaping of a groove in one of the cylindrical surfaces ofthe ring adapted to serve as a raceway for the balls. The ring isfinally heat-treated and ground to desired finish.

This method, however, suffers from certain disadvantages. The tubematerial is comparatively expensive, and in order to obtain the desireddimensions, working operations will bring about considerable losses ofmaterial. Simpler methods of producing bearing rings have been proposedin which a tubular element cut from a tube manufactured in conventionalmanner is used whereupon grooves are formed in the cylindrical surfacesby means of a suitable operation. Unworked tubes of this kind will,however, not be of satisfactory quality with respect toout-of-roundness, and variations in wall thickness, and are thereforenot well suited for manufacture of bearing rings having raceways formedby a rolling operation as extra working operations will be required toobtain a bearing component having the desired properties.

According to the present invention it is now proposed a novel method ofmanufacturing rolling bearing components which is characterized by thefollowing steps, forming a tubular member, cutting the tubular memberinto suitable lengths to constitute the required components, providingeach of said components with one or more circumferential grooves by arolling operation on the internal or external cylindrical surface,respectively, and/or likewise by rolling with at least one flangelocated at an angle to any of said cylindrical surfaces.

The invention will below be described with reference to the attacheddrawings, on which FIG. 1 schematically shows part of the workingoperations according to the method,

FIGS. 2 to 7 show various kinds of rolling operations according to theinvention,

FIG. 8 shows a bearing the race rings of which are designed according tothe method.

FIG. 1 shows the basic steps of obtaining the components, the portiondenoted by 1 shows the sheet blank in its original shape. The blankpreferably consists of a strip of sheet steel, and this is within theportion denoted by 2 by means of suitable automatically workingmachinery, not shown here, formed into a tubular member.

The right-hand part of this portion includes automatic weldingapparatuses for joining the juxtaposed edges of the sheet. Withinportion 3 the tubular member is cut into rings 4 of suitable lengths ofform the bearing components. A tubular component manufactured in thismanner has many advantages compared to a tube manufactured inconventional manner, noticeably very small deviations from the circularcross section and an even wall thickness. It is therefore possible toproduce rolling bearing components in finished shape solely by the stepsaccording to the invention.

FIGS. 2 to 7 show various forms of the last step of the manufacturingprocess, i.e. the rolling operation.

FIG. 2 shows the rolling of an outer ring 5 for a rolling hearing whichis to be provided with two flanges, the operation is performed asso-called outwardly directed rolling, the flanges beingpressed outwardsby means of a tool 6 working against an outer die, which preferably isdivided.

During rolling operation according to FIG. 3 the tubular component 8(shown in dotted lines) is mounted in a holder 9, whereupon the edges ofthe component by means of rolling tools 10 are forced inwards in such amanner that a bearing ring having two flanges is obtained.

FIGS. 4 and 5 show outwardly directed rolling for forming the ring. FIG.4 shows how a tubular component 12 is mounted in a holder 13 without anyinternal support. In order better to retain the component during therolling operation the holder preferably is provided with O-ring elements14. By means of the rolling tools 15 the edges of the component are bentin such a manner that a bearing ring having flanges 16 (denoted by dashlines) is obtained. In order to obtain an exact shape of the ring it maybe advantageous to provide a shallow groove to serve as bendingindication at the appropriate part of the ring. FIG.'5 shows an inwardlydirected rolling operation using an internal support. The tubularcomponent is mounted in a holder similar to that according to FIG. 4 andis at the portion to be bent supported by a rotating member 18 theflange or flanges being rolled down by means of a tool 19. Also in thisembodiment it may be advantageous to provide an indicating groove asmentioned in connection with FIG. 4. It is also possible to perform aninwardly directed rolling by using a fixed internal support. It isfurther possible to perfonn the operation as a combined rolling andpressing step. The rolling operations according to FIGS. 2 to 5 are notlimited to any definite angle between the cylindrical part of the ringand the flange, and it is possible to produce inner as well as outerring members for the bearing and provide with one or two flanges.

It is also possible to manufacture other types of bearing componentsaccording to the present method, for example cages for roller or needlebearings having slots for the rolling bodies. The sheet blank will thenbe provided with series of punched pockets. This blank is formed into aperforated tube, the edges are welded together and the tube is cut intocage elements of suitable length in such a manner that an annularunbroken portion remains at one or both ends of the element. In thismanner a cage of open or of closed type is obtained, thereafter therolling operation is performed in such a manner that the annular portionor portion is or are given a small inclination in relationship to theperforated cylindrical part of the cage.

FIG. 6 shows a rolling operation according to the invention during whichone or more raceways 20 by means of a tool 22 working in conjunction toa mandrel 23 are rolled into a ring member 31 which is adapted to serveas an inner ring of a ball bearing. In order to obtain a satisfactoryresult of an acceptable tolerance at 25 it is necessary that the memberis pressed against a fixed support at 24. With an inner ring producedaccording to this method the noticeable advantage is obtained that thering, when mounted on the shaft, will be in contact with the same onlyat the ridges denoted by 24, and appearing at the back of the raceways.In this manner fine grind tolerances at the ring and at the shaft,respectively, are eliminated. FIG. 7 shows the rolling of an outer ringfor a bearing of last-mentioned type. During this step the ring member26 is mounted in a fixed holder 27 and the raceway or raceways areformed by means of tools 28. The holder is provided with grooves 29adapted to accommodate the ridges formed during this operation. Theseridges will fulfill the same purpose as indicated in connection with theinner ring according to FIG. 6.

FIG. 8 shows a double-row ball bearing mounted in a small wheel andwhere the outer and inner ring, respectively, have been manufacturedaccording to the invention. In this design the body of the wheelpreferably is made of plastics, rubber or the like, whereby the body iscast or extruded directly onto the outer ring of the bearing. The ridgesof the outer ring described in connection with FIG. 7 will then aid inretaining the wheel body on the ring.

Iclaim:

l. A method of manufacturing rolling bearing components consisting ofthe steps of forming a tubular member by bending up a flat sheet andjoining the sheet at confronting edges, separating the tubular memberinto a plurality of annular rings, and simultaneously rolling andbending at least one flange at one end of said annular ring at groovedportions formed by rolling.

4. A method as claimed in claim I wherein the edges are joined bywelding.

5. A method as claimed in claim 3 wherein the rings are separated toprovide unbroken portions at least at one axial end of said pockets.

6. A method as claimed in claim 3 wherein the rings are separated toprovide unbroken portions at opposite axial ends of said pockets.

1. A method of manufacturing rolling bearing components consisting ofthe steps of forming a tubular member by bending up a flat sheet andjoining the sheet at confronting edges, separating the tubular memberinto a plurality of annular rings, and simultaneously rolling andbending at least one flange at one end of said annular ring at groovedportions formed by rolling.
 2. A method of manufacturing rolling bearingcomponents consisting of the steps of forming a tubular member bybending up a flat sheet and joining the sheet at confronting edges,separating the tubular member into a plurality of annular rings, andsimultaneously rolling and bending flanges at opposite ends of saidannular ring at grooved portions formed by rolling.
 3. A method asclaimed in claim 1 including forming the sheet blank with a series ofpunched pockets.
 4. A method as claimed in claim 1 wherein the edges arejoined by welding.
 5. A method as claimed in claim 3 wherein the ringsare separated to provide unbroken portions at least at one axial end ofsaid pockets.
 6. A method as claimed in claim 3 wherein the rings areseparated to provide unbroken portions at opposite axial ends of saidpockets.